Topical anesthetic

A drug applied to skin or a mucous membrane to reduce sensation in nearby tissues, usually by blocking nerve signals without injection.

Voltage-gated sodium channel: A membrane protein that opens in response to voltage changes and allows sodium ions to cross cell membranes. Most topical anesthetics reduce sensation by blocking these channels in sensory nerves.
Lidocaine: A widely used local anesthetic that reversibly blocks voltage-gated sodium channels. Topical lidocaine is used on skin and mucous membranes for localized pain or procedural comfort.
Infiltration anesthesia: Local anesthesia produced by injecting anesthetic into tissue around a target area. Injection bypasses the surface barrier and can numb deeper tissue more reliably.
Methemoglobinemia: A disorder in which oxidized hemoglobin cannot carry oxygen effectively. Benzocaine exposure can trigger this rare but serious complication, especially on mucosal surfaces.
Local anesthetic: A drug that reversibly blocks sensation in a limited body region without causing loss of consciousness. Topical anesthetics are local anesthetics delivered across a body surface.
Benzocaine: An ester local anesthetic used mainly in topical products for skin and mucous membranes. Its common oral and throat preparations illustrate topical use on mucosal surfaces.
Regional anesthesia: Anesthesia that blocks sensation across a larger body region by targeting nerves or nerve pathways. Topical anesthesia is a limited, noninvasive form of local rather than regional nerve blockade.
Lidocaine toxicity: Adverse effects caused by excessive lidocaine exposure, ranging from neurologic symptoms to cardiac complications. Excessive topical dosing can raise blood levels enough to produce systemic effects.
Stratum corneum: The outermost layer of the epidermis, formed by flattened dead cells embedded in lipids. On intact skin, this barrier limits how much anesthetic reaches nerve endings.
Prilocaine: An amide local anesthetic used alone or with lidocaine in topical preparations. Its combination with lidocaine is used to numb intact skin before some procedures.

Linked from 6 pages